How many megabytes does the video take for 3 minutes and 5 minutes? What is the general format of video? Please, I want to hold a photo contest, but I don't know anything about it. .

A video of 3-5 minutes is only about 18m-50m, which is related to format clarity.

Video refers to various technologies that capture, record, process, store, transmit and reproduce a series of still images in the form of electrical signals. When the continuous image changes more than 24 frames per second, according to the principle of visual persistence, the human eye cannot distinguish a single static picture; It looks like a smooth and continuous visual effect, and such a continuous picture is called a video.

Video technology was originally developed for TV system, but now it has developed into various formats to facilitate consumers to record videos. With the development of network technology, recorded video clips exist on the Internet in the form of streaming media, which can be received and played by computers. Video and movies belong to different technologies. The latter uses photography to capture dynamic images into a series of still photos.

Scanning transmission

Video can be transmitted by progressive scanning or interlaced scanning. Interlaced scanning is a method to improve image quality in the early years when broadcasting technology is underdeveloped and bandwidth is very low (please refer to its main item for technical details).

NTSC, PAL and SECAM are all interlaced scanning formats. I is often used to represent interlaced scanning in the abbreviation of video resolution. For example, the resolution of PAL format is often written as 576i50, where 576 represents the number of vertical scanning lines, I represents interlaced scanning, and 50 represents 50 fields per second (half of the number of scanning lines in a picture).

In the progressive scanning system, every time the image is updated, all scanning lines will be refreshed. This method consumes more bandwidth, but it can reduce the flicker and distortion of the picture.